This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Human vWF is an ultra large vascular glycoprotein, and dysfunction of the correct multimer formation will cause prolonged bleeding. We are working on determining the structure of domains of this protein.